1. Field of the Invention
This invention relates, in general, to computer systems and, more specifically, to content distribution of data information to remote computer users.
2. Description of the Prior Art
Distribution of information by digital data is becoming common with advances in computer and telecommunications network technologies, especially the Internet and the World Wide Web (WWW). The data transmitted over the network can represent various types of information, including text, graphics, image, video, and voice (so called multimedia data). The multimedia data can be in both static files and in executable files, and both types are included herein when "files" are specified. Since these multimedia data files are usually large, it requires a considerable amount of time to retrieve and transmit them over the network from a data content server to end users. Also, since a large number of users are usually involved when the network is the Internet, time responsive and efficient content delivery is critical for satisfactory Internet and web services. Thus, it is desirable, and an object of this invention, to provide a system with a new architecture which enhances the speed and efficiency of multimedia data content distribution.
One type of data content distribution becoming increasingly popular is that of publishers distributing their published works online over a suitable communications network, such as the World Wide Web (WWW) on the Internet. This has certain advantages to both the user and the publisher over fixed hard-copy distribution methods, and even over some more modern digital methods like CD-ROM. However, traditional methods of implementing data file distribution over the WWW does not lead to the efficiency desired for these types of materials. Compared to many other types of data files, publisher's data files have "well-composed contents," meaning that the contents is relatively mature and does not need frequent changes made in the files. The data files containing the contents of current books, journals, magazines, reports, newspapers, etc., would be examples of well-composed contents files. After going through the editorial process and being stored for distribution, their contents rarely needs to be changed.
According to existing prior art techniques, data files for distribution to remote computer users are usually located at a specific computer site, or source server. When any user on the system to which the server is connected wants to access or download a data file, the data is sent from the server to the user, over the communications network and through any intermediate servers. One difficulty with these systems is that when users are distant from the content server, such as is the case with global services to different geographical areas, the latency of data transmission time is a factor in satisfactory performance. Also, with such a system, there is an increase in network load which possibly slows down other services. On the other hand, users in a corporate LAN environment need to go through a gateway to reach remote servers. The gateway becomes a bottle-neck for performance. Therefore, it is desirable, and it is an object of this invention, to provide a content distribution system which maximizes access speed for remote users, reduces network load, and provides high speed accessibility for LAN environment users in reaching outside servers.
The system of this invention uses a combination of a central or global server and multiple local servers to implement the invention in a way that uses the well-composed nature of the data to advantage in preserving the resources of the network. Some prior art references have also used multiple level networks to carry out some of their objectives. European Patent Application, number 91301187.0, publication number 0 447 038 A2, published on Sep. 18, 1991, titled "A System for Establishing a Communication Path in a Closely Coupled Computer System" discloses a system wherein different levels of servers are used. The disclosure teaches a global server coupled to several local servers by a communications path. However, this system is structured for message communications in a closely coupled computer system, not for efficient data file distribution between a global server and many end users over a network as open as the Internet. One of the primary functions of the system described in the referenced application is to use a destination intermediation unit (11) to aid in the process of establishing a communication path which insures security of the message being delivered.
European Patent Application, number 93301715.4, publication number 0 615 362 A1, published on Sep. 14, 1994, titled "Network Analysis Method" discloses an analysis method wherein, what it describes as local and global servers, are identified. The method involves processing traffic data by removing traffic associated with nodes identified as acting as global servers, and using the remaining traffic to identify nodes acting as local servers. Upon the local servers being identified, the network analysis method carries out further processing to make suggestions as to whether any local servers should be moved to another segment or whether a segment should be split. While this technique may provide some important analysis methods to enhance and/or control a multi-level network system, it does not present the many features of the present invention which utilize a two-level arrangement of servers to perform an improved system of data file distribution to remote users.